References?

I have a lot of people ask me for references and I feel bad cause I often ask the same people I’ve babysat for if I can put their number down and often the job doesn’t even end up working out. Does anyone have the past families they’ve worked for send a note that I can use repeatedly as a reference? It’s just frustrating many people want them upfront and when the schedule doesn’t work out I’ve just wasted the time of my old employer by making them have a whole call with this random person. I definitely understand why people want references I just wish they’d only ask when they’re serious about hiring me.